Capillary instability of a two-layer annular film: an airway closure model
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| Název: | Capillary instability of a two-layer annular film: an airway closure model |
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| Autoři: | O. Erken, F. Romanò, J.B. Grotberg, M. Muradoglu |
| Přispěvatelé: | Administrateur Ensam, Compte De Service, Laboratoire de Mécanique des Fluides de Lille (LMFL), Erken, Oğuzhan, Muradoğlu, Metin (ORCID 0000-0002-1758-5418 & YÖK ID 46561), Romano, F., Grotberg, J. B., Graduate School of Sciences and Engineering, College of Engineering, Department of Mechanical Engineering |
| Zdroj: | Journal of Fluid Mechanics |
| Informace o vydavateli: | Cambridge University Press (CUP), 2022. |
| Rok vydání: | 2022 |
| Témata: | 0301 basic medicine, 0303 health sciences, Sciences de l'ingénieur: Mécanique: Mécanique des fluides, Physics, Mechanical Engineering, Pulmonary fluid mechanics, [SPI.MECA.MEFL] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Mechanics, Condensed Matter Physics, 03 medical and health sciences, Fluids and plasmas, Mechanics of Materials, Pulmonary Fluid mechanics |
| Popis: | Capillary instability of a two-layer liquid film lining a rigid tube is studied computationally as a model for liquid plug formation and closure of human airways. The two-layer liquid consists of a serous layer, also called the periciliary liquid layer, at the inner side and a mucus layer at the outer side. Together, they form the airway surface liquid lining the airway wall and surrounding an air core. Liquid plug formation occurs due to Plateau–Rayleigh instability when the liquid film thickness exceeds a critical value. Numerical simulations are performed for the entire closure process, including the pre- and post-coalescence phases. The mechanical stresses and their gradients on the airway wall are investigated for physiologically relevant ranges of the mucus-to-serous thickness ratio, the viscosity ratio, and the air–mucus and serous–mucus surface tensions encompassing healthy and pathological conditions of a typical adult human lung. The growth rate of the two-layer model is found to be higher in comparison with a one-layer equivalent configuration. This leads to a much sooner closure in the two-layer model than that in the corresponding one-layer model. Moreover, it is found that the serous layer generally provides an effective protection to the pulmonary epithelium against high shear stress excursions and their gradients. A linear stability analysis is also performed, and the results are found to be in good qualitative agreement with the simulations. Finally, a secondary coalescence that may occur during the post-closure phase is investigated. |
| Druh dokumentu: | Article Other literature type |
| Popis souboru: | application/pdf; pdf |
| Jazyk: | English |
| ISSN: | 1469-7645 0022-1120 |
| DOI: | 10.1017/jfm.2021.1126 |
| Přístupová URL adresa: | https://www.cambridge.org/core/services/aop-cambridge-core/content/view/989C26EA98823BA8A98F861146F2E349/S0022112021011265a.pdf/div-class-title-capillary-instability-of-a-two-layer-annular-film-an-airway-closure-model-div.pdf http://hdl.handle.net/10985/24444 http://cdm21054.contentdm.oclc.org/cdm/ref/collection/IR/id/10225 https://aperta.ulakbim.gov.tr/record/258557 |
| Rights: | CC BY |
| Přístupové číslo: | edsair.doi.dedup.....95c8742f11656dc3db39be3dc28ce8dd |
| Databáze: | OpenAIRE |
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Nájsť tento článok vo Web of Science | Abstrakt: | Capillary instability of a two-layer liquid film lining a rigid tube is studied computationally as a model for liquid plug formation and closure of human airways. The two-layer liquid consists of a serous layer, also called the periciliary liquid layer, at the inner side and a mucus layer at the outer side. Together, they form the airway surface liquid lining the airway wall and surrounding an air core. Liquid plug formation occurs due to Plateau–Rayleigh instability when the liquid film thickness exceeds a critical value. Numerical simulations are performed for the entire closure process, including the pre- and post-coalescence phases. The mechanical stresses and their gradients on the airway wall are investigated for physiologically relevant ranges of the mucus-to-serous thickness ratio, the viscosity ratio, and the air–mucus and serous–mucus surface tensions encompassing healthy and pathological conditions of a typical adult human lung. The growth rate of the two-layer model is found to be higher in comparison with a one-layer equivalent configuration. This leads to a much sooner closure in the two-layer model than that in the corresponding one-layer model. Moreover, it is found that the serous layer generally provides an effective protection to the pulmonary epithelium against high shear stress excursions and their gradients. A linear stability analysis is also performed, and the results are found to be in good qualitative agreement with the simulations. Finally, a secondary coalescence that may occur during the post-closure phase is investigated. |
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| ISSN: | 14697645 00221120 |
| DOI: | 10.1017/jfm.2021.1126 |